Linkage for multiple carburetor installation



April 1962 o. v. EDELBROCK, JR 3,030,819

LINKAGE FOR MULTIPLE CARBURETOR INSTALLATION Filed Sept. 22, 1960 2 Sheets-Sheet 1 INVENTOR. 30 O. VICTOR EDELBROCK, JR.

BY 5 r5 ATTORNEYS April 24, 1962 I o. v. EDELBROCK, JR ,8

LINKAGE FOR MULTIPLE CARBURETOR INSTALLATION Filed Sept. 22, 1960 2 Sheets-Sheet 2 INVENTOR. 0. VICTOR EDELBROCK, JR. FIG. 6.

BY W

ATTORNEYS indicated 10.

each end of rockshaft 16 are crank arms 17 and 18.

3,030,819 LINKAGE FOR MULTIPLE CARBURETGR WSTALLATIGN Otis Victor Edelbroclr, Jr., Los Angeles, Calif., assiguor to Edelbrock Equipment (10., Los Angeles, Calif, a corporation of California Filed Sept. 22, 1960, Ser. No. 57,801 7 Claims. (Cl. 74-471) This invention relates generally to a linkage assembly for a multiple carburetor installation on an internal combustion engine.

More specifically this invention relates to linkage means for actuating multiple carburetors in synchronism or in predetermined sequential order, as desired.

It is an object, therefore, of this invention to provide a novel form of linkage assembly for a multiple carburetor installation.

It is a further object to provide a linkage assembly which can be adjusted to actuate one or two carburetors for small throttle opening and to cause the remaining carburetors to be actuated at a definite adjustable throttle setting during greater power demand conditions.

Another object is to provide a linkage system for actuating a plurality of carburetors arranged in two rows on an internal combustion engine, the linkage system including a transverse rockshaft having crank arms at opposed ends thereof, link-connected to actuate all of the carburetors in one row.

Another object is to provide a novel form of linkage system for operating a multiple carburetor installation, which linkage system can be furnished in kit form for attachment to an existing carburetor installation.

Further objects and advantages of this invention will be apparent from the following specification taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a side elevation showing a multiple carburetor assembly comprising a preferred embodiment of this invention.

FIGURE 2 is a plan view thereof.

FIGURE 3 is a partial side elevation showing one position of the various control elements of this inven- .tion during the sequence of operations thereof.

FIGURE 4 is another partial side elevation showing another position of said control elements.

FIGURE 5 is a sectional view taken substantially along lines 55 of FIGURE 2.

FIGURE 6 is a side elevation showing a modified form of the present invention.

Referring to the drawings, a plurality of carburetors .for an internal combustion engine are diagrammatically Said carburetors 10 are mounted on a manifold 11 in two parallel rows. The butterfly valves 12 which control, the actual flow of the air-fuel mixture into the manifold 11 are pivotally mounted in said carburetors 1t} and fixed on pivot shafts 13 in the usual manner. Said pivot shafts 13 project exteriorly of the housings ,of carburetors 10 so that actuating lever arms may be attached thereto to operate said butterfly valves, as will be more completely described below. v

A supporting bracket 14 comprising a stationary tube 15 provided with mounting tabs 15a is secured to one of the rear carburetors 10a as shown in FIGURE 2. Extending through said tube 15 is a transverse rockshaft 16 suitably journaled to rotate in said bracket 14. Aflixed to A control rod 19 may be attached to either end of crank arm 17 as desired, depending upon whether the rod 19 is to move to the right to open the carburetors 10 or whether said rod 19 is to move to the left. Since crank arms 17 and 18 are secured to rockshaft 16, and move simultaneously therewith, no provisions for a control rod are needed for crank arm 18.

A shoulder stud 20 is pivotally secured to crank arm 17 and a primary actuating rod 21 has one end adjustably secured to said shoulder stud. The other end of primary actuating rod 21 is adjustably secured to shoulder stud 22 which is in turn pivotally mounted to lever arm 23 at a point midway between the extremities thereof. Said lever arm 23 has one extremity secured to shaft 13 of the center carburetor 10b. At the other extremity of lever arm 23 there is another shoulder stud 24 pivotally mounted thereto. A secondary motion shaft 25 has one extremity adjustably secured in said shoulder stud 24, and has a bend at 26. The foremost extending portion of secondary actuating rod 25 has an adjustable stop means 27 attached thereto. The rod 25 extends through an enlarged aperture 28 in shoulder stud 29 as may best be seen in FIGURES 2 and 5. The aperture 28 is made somewhat larger than the diameter of the shaft 25 to allow said shaft to move freely therein. The shoulder stud 29 is pivotally secured to lever arm 30 which is in turn secured to shaft 13 of the front carburetor. An adjustable safety stop or collar 31 is slidably attached to rod 25.

The shoulder stud 29 also has a second aperture 32 in Which is adjustably secured a tie rod 33. Said tie rod 33 extends back to the rear carburetor 10a and is adjustably secured in shoulder stud 34 which is pivotally attached to lever arm 35. The lever arm 35 is fixed to the butterfly valve shaft 13 of carburetor 10a. A spring 36 is connected in tension between lever arm 34 and lever arm 23.

The linkage used to actuate the second row of carburetors is driven by the crank arm 18 and aside from the configuration of said arm 18 the linkage itself is substantially identical to that already described, and hence, no further description is warranted. The linkage system described in this invention is applicable to a single row carburetor installation in which the crank arm 18 is not used. However, the unique application of the bracket 14 and the crank arms 17 and 18 greatly facilitates coordination of operation of two banks of carburetors.

The sequential operation of this progressive linkage is best described referring to FIGURES 1, 3 and 4. In FIGURE 1 it is seen that all the butterfly valves 12 are in the closed position, at which the carburetors are in their idling position. As the accelerator pedal (not shown) is depressed, the control rod 19 moves to the right, pulling rod 21 to the right, which causes the lever arm 23 to rotate clockwise, opening the butterfly valve 12 of the center carburetor. During the rotation of lever arm 23 the secondary actuating rod 25 will also move rearwardly and will slide in the aperture 28 of shoulder stud 29, until the stop 2'7 abuts against said shoulder stud 29 as shown in FIGURE 3. The point at which said stop 27 reaches this position is readily adjustable as desired and in FIGURE 3 is shown to be approximately at half throttle opening. During this period of closed-to-halfopen throttle, it is seen that only the center carburetors in each row are supplying fuel to the engine, while the other carburetors remain in idle position. As the control rod 19 continues to move to the right, the stop 27, acting through rod 25, pulls against the shoulder stud 29 causing lever arm 30 to rotate clockwise. The operating rod 33 is also secured to shoulder stud 29 and the rotation of lever arm 30 causes the simultaneous rearward movement of tie rod 33 which in turn causes the clockwise rotation of lever arm 35. The ratio of the effective lever arms 30 and 35 to the effective lever arm 23 is such as to cause the two end carburetors to open more quickly than the center carburetor and they can be adjusted to reach full throttle at the same time that the center carburetor does. The full throttle position is shown in FIGURE 4.

When the accelerator pedal is released, causing the control rod 19 to return to the left, the lever arm 23 will follow the movement to the left since it is in direct connection thereto. Accordingly, the throttle of the center carburetor will close immediately. The action of the spring 36 is such as to cause the outboard carburetors to follow the center carburetor in closing. However, if such does not taken place, or in the event that these carburetor throttles stick open and the force of the spring 36 is not sufiicient to pull them closed, the safety stop 31 will push them closed as the rod 25 slides through the aperture 28 in shoulder stud 29.

A modified form of this invention is shown in FIGURE 6 wherein a non-progressive linkage is shown. The crank arm 17a is similar to that previously described above. A rod 40 has one end pivotally attached to crank arm 17a and the other end thereof is pivotally attached to connector 41. A tie rod 42 is secured to this connector 41 and extends through shoulder studs 43, 44 and 45 of each carburetor. These shoulder studs are pivotally attached to lever arms similar to lever arms 30 and 35 of the previously described device. A spring 46 is connected in tension from one of the lever arms to a fixed point to provide a return force which will close all carburetors simultaneously. The position of the parts is shown in phantom lines in the fully opened throttle position and shows the approximate position of the various components of this modification in such a position. In this modification all carburetors are actuated in synchronism. This linkage is applicable to a three-carburetor installation as well as to a six-carburetor installation comprising two banks of three carburetors each, as previously described.

While particular embodiments of the present invention have been shown and described, changes and modifications will become apparent to those skilled in the art, and it is the aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. A linkage system for operating the pivot shafts ofa plurality of carburetors operatively mounted in two rows on an internal combustion engine comprising, in combination: a rockshaft having first and second crank arms fixed thereto, means adapted to be fixed relative to the carburetors for pivotally supporting said rockshaft, means whereby the pivot shafts of the carburetors in each row may be actuated from one of said crank arms respectively, said means including a plurality of lever arm shaft, respectively, link means connecting one of the assemblies, one adapted for connection to each pivot lever arm assemblies to one of said crank arms, linkage means including a lost motion sliding connection conmeeting the latter said lever arm assembly to a second lever arm assembly, a tie rod pivotally connecting said second lever arm assembly to a third lever arm assembly for movement in unison, and resilient means acting to cause turning movement of said first and third lever arm assemblies toward closed position.

2. A linkage system for operating the pivot shafts of a plurality of carburetors operatively mounted in two rows on an internal combustion engine, comprising, in combination: a rockshaft having first and second crank arms fixed thereto, means adapted to be fixed relative to the carburetors for pivotally supporting said rockshaft, means whereby the pivot shafts of the carburetors in each row may be actuated from one of said crank arms, respectively, said means including a plurality of lever arm assemblies, one adapted for connection to each pivot .shaft, respectively, a primary actuating rod having one end pivotally attached to one of said crank arms and the other end pivotally attached to one of said lever arm assemblies at a location intermediate the ends thereof, a secondary actuating rod having one end pivotally secured to the latter said lever arm assembly, a portion of said secondary actuating rod being slidably journaled in a second lever arm assembly, stop means on said secondary actuating rod adjustably positioned to limit the extent of sliding movement between said actuating rod and said lever arm assembly, a tie rod having one end pivotally attached to said second lever arm assembly and having the other end pivotally attached to a third lever arm assembly to connect said second and third lever arm assemblies for movement in unison, and resilient means acting to cause turning movement of said first and third lever arm assemblies toward closed position.

3. A linkage system for operating the pivot shafts of a plurality of carburetors operatively mounted in two rows on an internal combustion engine, comprising, in combination: a rockshaft having first and second crank arms fixed thereto, means adapted to be fixed relative to the carburetors for pivotally supporting said rockshaft, means whereby the pivot shafts of the carburetors in each row may be actuated from one of said crank arms, respectively, said means including a plurality of lever arm assemblies, one adapted for connection to each pivot shaft, respectively, a primary actuating rod having one end pivotally attached to one of said crank arms and the other end pivotally attached to one of said other arm assemblies at a location intermediate the ends thereof, a secondary actuating rod having one end pivotally secured to the latter said lever arm assembly at a location of greater radial distance than the pivotal mounting of the said primary actuating rod, a portion of said secondary actuating rod means slidably journaled in a second lever arm assembly, stop means on said secondary actuating rod adjustably positioned to limit the extent of sliding movement between said actuating rod and said lever arm assembly, a tie rod pivotally attached to said second lever arm assembly and having one or more other lever arm assemblies pivotally attached along its length for movement in unison of all such lever arm assemblies connected to said tie rod, and resilient means acting to cause turning movement of all said lever arm assemblies toward a closed position.

4. A linkage system for operating the pivot shafts of a plurality of carburetors operatively mounted in a row on an internal combustion engine, comprising, in combination: a plurality of lever arm assemblies, one adapted for connection to each pivot shaft, respectively, a primary actuating rod having one end pivotally attached to one of said lever arm assemblies at a location intermediate the ends thereof, a secondary actuating rod having one end pivotally secured to the latter said lever arm assembly and having a lost-motion connection with a second lever arm assembly, and a tie rod pivotally connecting said second lever arm assembly to a third lever arm assembly for effecting movement in unison in one direction.

5. The combination set forth in claim 4, wherein resilient means are provided to move the tie rod in the other direction.

6. The combination set forth in claim 4, wherein stop means are provided on said secondary actuating rod to limit the extent of movement of said lost-motion connection.

7. A linkage system for operating the pivot shaft of a plurality of carburetors operatively mounted in a row on an internal combustion engine, comprising, in combination: a plurality of lever arm assemblies, one adapted for connection to each pivot shaft, respectively, a primary actuating rod having one end pivotally attached to one of said lever arm assemblies at a location intermediate the ends thereof, a secondary actuating rod having one end pivotally secured to the latter said lever arm assembly, a portion of'said secondary actuating rod being slidably journaled in a second lever arm assembly, a stop means on said secondary actuating rod adjustably positioned to limit the extent of sliding movement between said actuating rod and said second lever arm assembly, 2,811,862 Libby Nov. 5, 1957 a tie rod having one end pivotally attached to said second 2,878,331 Fjellstedt Mar. 17, 1959 lever arm assembly and having the other end pivotally attached to a third lever arm assembly to connect said FOREIGN PATENTS second and third lever arm assemblies for movement in 5 57 5 Great Britain May 10 1922 unison, and resilient means acting to cause turning movement of said first and third lever arm assemblies toward OTHER REFERENCES closed posltlo I. C. Whitney & C0., Catalog No. 154, copyright 1959,

References Cited in the file of this patent New Ball Bearing Throttle Linkage, page 98, Throttle UNITED STATES PATENTS 10 Linkage Assemblies, page 98.

2,420J925 Wirth May 20, 1947 

